1,721,059 research outputs found
Studio delle relazioni tra i composti volatili emessi dall'uomo e le patologie
Get PDFL’obiettivo di questa tesi è lo studio dei composti volatili che caratterizzano l’odore della pelle. E’ noto come alcune patologie modificano i processi metabolici e conseguentemente la composizione chimica dello spazio di testa di prodotti del metabolismo come urine, espirato, sudore etc. In questo lavoro un sistema olfattivo artificiale basato su sensori di gas a variazione di massa è stato utilizzato per lo studio di patologie della pelle attraverso i composti volatili prodotti nella traspirazione della pelle stessa. In particolare sono state studiate due patologie: il melanoma direttamente coinvolto nella traspirazione della pelle e il tumore del seno. Quest’ultimo non si può propriamente definire una patologia della pelle ma attraverso la traspirazione potrebbe essere rilevato. Per meglio comprendere questi meccanismi nell’ultima parte del lavoro è stata monitorata la crescita di alcune linee cellulari, relative a malattie della pelle. Tali linee cellulari sono state studiate dapprima in vitro e successivamente in vivo inoculandole in cavie da laboratorio. Questi esperimenti sono stati eseguiti
utilizzando un naso elettronico e un Gas Cromatografo con Spettrometro di Massa
(GC/MS). I risultati ottenuti incoraggiano a studiare maggiormente la correlazione tra
gli odori e altre patologie come una nuova metodologia per la diagnosi precoce e
non-invasiva.In this thesis, the volatile compounds surrounding the body have been
analysed. It is known that some pathologies modify a number of metabolic
processes and this results in a modification of the chemical composition of
headspace of some products as urine, breath, sweat. In particular the aim of this
work is to apply an artificial olfactory system based on gas sensor array to study
some pathologies affecting the skin and potentially revealed by volatile
compounds during the patient transpiration . In this study two pathologies have
been investigated, the melanoma obviously directly involved in skin transpiration,
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and breast cancer which is not properly a skin disease, but from skin transpiration
could be revealed. To better clarify these mechanisms in the last part of this work
it has been described an experiment in which the growth of some cell lines,
related to skin diseases has been monitored; this experiment has been conducted
with an electronic nose and a GC/MS firstly in cell coltures, and then in vivo on
mice inoculated with the measured cells.
The results of these experiments encourage to better investigate the role of
odour in the human pathologies as a possible methodology of ‘non-invasive’ early
diagnosis
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
MNP-based sensor development to evaluate food quality and safety
No full textAmong them all, sensor systems are new
analysis methods that present environmental and economic sustainability
features. These devices contribute significantly to simplifying measurement
processes and to the reliability and precision of measurement results.22 In
the manufacturing and agro-food sectors, this instrumentation is widely
used in monitoring production processes, in food safety and quality control
and to simplify the operator’s work.23 However, the use of magnetic
nanoparticle-based sensors, in this manufacturing field, are not yet widespread.
This chapter highlights the recent applications of these devices in
the agri-food field and their applications in food quality and safety along the
entire supply chain
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
Equivalent electric circuits for chemical sensors in the Langmuir regime
No full texttThis paper presents an equivalent electric circuit model that describes adsorption-desorption processesoccurring on bio and chemical sensor surfaces under the Langmuir hypothesis and considers the followingpractical case: the pressure or concentration of the particles in the test chamber is not perturbed bythese processes and keeps its initial value, as in the cases of relatively high pressure or concentrationvalues with zero molecular flow, or in the presence of a molecular flow at any pressure or concentrationvalue. It is also pointed out that the equivalent circuit for Langmuir adsorption is similar to the circuitproposed for enzymatic reactions. Even if this work essentially covers theoretic aspects, a way is suggestedfor the possible experimental determination of both adsorption-desorption parameters and adsorption-desorption site density
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